Location: Sugarbeet and Potato ResearchTitle: Methyl jasmonate alleviates drought stress in young sugarbeet (Beta vulgaris L.) plants
|LAFTA, ABBAS - North Dakota State University|
|LI, GUOLONG - Inner Mongolian Agriculture University|
|DECKARD, EDWARD - North Dakota State University|
|KHAN, MOHAMED - North Dakota State University|
|FINGER, FERNANDO - Universidade Federal De Vicosa|
Submitted to: Journal of Agronomy and Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/29/2018
Publication Date: 6/25/2018
Citation: Fugate, K.K., Lafta, A.M., Eide, J.D., Li, G., Lulai, E.C., Young, L.L., Deckard, E.L., Khan, M.F., Finger, F.L. 2018. Methyl jasmonate alleviates drought stress in young sugarbeet (Beta vulgaris L.) plants. Journal of Agronomy and Crop Science. https://doi.org/10.1111/jac.12286.
Interpretive Summary: Drought is the major cause of yield loss for the sugarbeet crop and little can be done to minimize these losses since sugarbeets are mostly produced without irrigation and sugarbeet varieties with tolerance to drought do not exist. Plants naturally have defense mechanisms to protect themselves from the stress caused by drought, and these defenses are turned on by the plant hormone, methyl jasmonate (MeJA). Research, therefore, was conducted to determine whether applying MeJA could turn on plant natural defenses and protect plants from drought. Drought reduced plant weight, water content, and the rate of photosynthesis and increased accumulation of proline and betaine, two chemicals that plants produce to protect themselves from stress. MeJA treatment allowed plants to maintain greater shoot weight, water content, and photosynthesis rates under drought conditions. MeJA also increased proline accumulation under severe drought conditions. Because MeJA treatment effectively protected young sugarbeet plants from drought, this commercially available chemical could potentially be used by sugarbeet growers to reduce the economic loss caused by dry weather conditions during early sugarbeet production.
Technical Abstract: Drought is the major cause of yield and economic loss for the sugarbeet crop. Mechanisms to reduce drought stress, however, are lacking since sugarbeets are largely produced without irrigation and drought tolerant varieties are not available. Since jasmonates are implicated in plant drought stress responses, research was conducted to determine whether methyl jasmonate (MeJA) could mitigate drought effects on sugarbeet. Fourteen day old plants were treated with 0, 0.01, 0.1, 1, or 10 µM MeJA. Seven days later, half of the plants were drought stressed by withholding water, while control plants continued to receive water. Drought caused leaf relative water content (RWC), shoot fresh and dry weights, net photosynthetic rate (Pn), transpiration rate (EVAP), stomatal conductance (Gs), water use efficiency (WUE), and PSII quantum efficiency to decline and substomatal CO2 concentration (Ci) and proline and betaine concentrations to increase. MeJA, at 1 and 10 µM, reduced moderate and severe drought effects on RWC, Pn, Ci, and WUE, altered drought-induced changes in proline accumulation, but had no effect on Gs, EVAP, or betaine accumulation. Results indicate that MeJA delayed plant dehydration and protected the photosynthetic apparatus from drought-induced impairment. Exogenous application of MeJA, therefore, alleviates drought stress on young sugarbeets and may provide a tool to reduce the economic loss caused by dry conditions during early crop production.